make mandb handling runner-safe and refine apt install benchmarks#7

[Vinodha-kumar]

The apt-install action and benchmark workflow to handle GitHub runner changes around man-db and to make benchmark comparisons fairer.

Relates to #7

[Copilot]

Pull request overview

Copilot reviewed 2 out of 2 changed files in this pull request and generated no new comments.

Suppressed comments (3)

.github/workflows/benchmark.yml:98

• This setting does not apply to the cache: true path: action.yml only forwards packages, and cache-apt-pkgs-action v1.4.3 performs a normal apt-fast install without --no-install-recommends. The plain and no-cache jobs suppress recommendations, so the three benchmarks can install different package sets and are not like-for-like. Align the install semantics across all jobs or make the cached path honor this input.

          cache: true
          apt_update: true
          recommends: false
          mandb: false

action.yml:47

• command -v follows the caller-controlled PATH, but the package's trigger invokes the system mandb executable. If an earlier shim/custom installation exists, this overwrites that file while leaving /usr/bin/mandb active, so mandb: false no longer disables the trigger. Check and replace the package-owned path directly.

        if command -v mandb >/dev/null 2>&1; then
          MANDB_PATH="$(command -v mandb)"
          echo "mandb found at ${MANDB_PATH}; stubbing to /bin/true"
          sudo ln -sf /bin/true "${MANDB_PATH}"

.github/workflows/benchmark.yml:34

• The baseline should stub the package-owned executable rather than whichever mandb happens to appear first in PATH; dpkg's man-db trigger targets the system executable, so a custom PATH entry would leave updates enabled and invalidate baseline parity.

This issue also appears on line 95 of the same file.

          if command -v mandb >/dev/null 2>&1; then
            sudo ln -sf /bin/true "$(command -v mandb)"